Dental bracket-engine.



J. F. HAMMOND. DENTAL BRACKET ENGINE. APPLICATION FILED Arima, 190s.

vPatented Mar.1,1910.

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TOI-1N F. HAMMOND, 0F PRINCE BAY, NEWYORK, ASSIGNOR 'IO THE S. S. WHITE DENTAL MFG. CO., OF PHLADELPHIA, PENNSYLVANIA.

DENTAL BRACKET-ENGINE.

esame.

To all whom it may concern:

Be it known that I, JOHN F. HAMMOND, a citizen of the United States, residing in Prince Bay, in the county of Richmond and State of New York, have invented a certain new and useful Improvement in Dental Bracket-Engines; and l do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it ap pertains to make and use the same.

My invention relates to dental bracket engines and my object is to provide a simple yet strong engine of this class having ample range and freedom of movement and in which there will be no interference between the driving belt or cord used thereon.

My improvement consists in certain features of construction indicated in the accom panying drawing, described in the following specification and pointed out in the claims at the conclusion thereof.

In said drawings Figure l is a view in side elevation of my improved bracket engine. Fig. 2 is a top or plan view thereof. Fig. 3 is a central longitudinal section view on a larger scale than the preceding views of the head of said engine. Fig. 4.- is a view of said head on the line 4-4 of Fig. 3, looking inwardly. Fig. 5 is a section on the line 5 5 of Fig. 3, looking outwardly, this view being at a right angle to said Fig. 3. l

My improved engine, generally speaking, comprises a supporting arm consisting of two sections A and A1; an extensible bracket arm also consisting of two sections B and B1; a motor C; an engine head F, F2 and G; a flexible shaft D, and handpiece E.

The first part of my invention relates to the supporting arm A, A1 and the manner of connecting the motor C and bracket arm B, B1 thereto. |The inner section A of said arm projects rigidly from a wall plate A2 which serves as a means for securing said arm to a wall. To this rigid inner section A `of the arm the outer section A1 is connected by a vertical pivot a which permits of said outer section being swung horizontally. Formed on the motor C is an ear or lug c which is placed between the forked extremity al of the outer section A of the support- Specieation of Letters Patent.

Application led April 29, 1908.

Patented Mar. l., i910. Serial No. 430,005.

ing arm, a screw C1 being used to hold and clamp the parts in position. In this way the motor C has vertical rocking connection with the supporting arm by way of `a frictional clamp pivot. The bracket arm composed of the extensible or telescopic sections B and B1 is rigidly connected directly with the motor at I) to one side of the pivotal connection c between said motor and the supporting arm, and extends in a line which intersects the axis of the motor and the axis of the pivot c. The outer section A1 of the supporting arm is curved outwardly and downwardly, whereby the pivotal connection c between said arm and the motor is considerably below the inner end of the inner section A of the supporting arm and also below and in advance of the pivotal connection a between the two sections of said arm, and whereby also the motor has ample room to move upwardly when the bracket arm is swung downwardly, movement of said arm in this direction only being limited by the motor coming in contact with the supporting arm. By this construction the weight of the motor countenbalances, or nearly counter-balances, the weight of the bracket arm and the parts carried thereby; the bracket arm maybe moved into a substantially vertical position where it lies up against the wall out of the way when not in use; it may be moved into any other vertical position to best suit the needs of the operator; and said arm may also be moved horizontally to any desired extent. In short, this exceedingly simple and strong construction provides free and ample adjustment of the bracket arm, which will temporarily remain in any position to which it may be moved.

The second part of my invention relates to- Vdesired position.

is a driving pulley I. For the purpose of properly supporting and guiding the driving cord or belt J which passes about the driving and driven pulleys, a series of guide or idle pulleys are provided as follows :r-Y single pulley K is mounted on the side of the bracket arm at or near the outer end of the inner section B and is adjustable along said section in order to alter or adjust the tension of the driving cord, a screw Kl being employed for securing the pulley in any Another single pulley L is supported under the said inner section of the arm, this pulley being carried by the outer section B1 which, as before stated, telescopes in the inner section. Finally, a pair of pulleys M are mounted on the inter- Vmediate member F2 of the engine-head. The

driving cord or belt passes from the driving pulley I to the idle pulley K, to the idle pulley L, then to one of the idle pulleys M; then after passing about the driven pulley H it passes to the other pulley M and from thence back to the driving pulley I. Pulleys K and L are arranged after the manner of the well known compensating pulleys commonly used upon this class of dental engines. Their object is to maintain the proper tension on the driving cord when the --and the distance between the pulleys H and I thereby lessened, the distance between the pulleys K and L is correspondingly lengthened.

YFor the purpose of giving flexibility to the connection between the end of the bracket arm and the engine arm, thereby permitting the latter great freedom of movement, the following joints are provided in the engine head: The inner member F is swiveled at f to the outer end of the bracket arm; the intermediate member F2 is pivoted at f1 to an angular extension Fl of the inner member, so that the intermediate member may rock laterally in respect to the inner member; and the outer member Gr of said head is pivoted at g to said intermediate member, the pivot g being disposed at a right angle to the pivot f1 and permits of the outer member G being rocked in line with the longitudinal axis of the bracket arm. If desired the outer member G may be made in two parts G and G1 having swivel connection at g1. With a head provided with these or equivalent joints, the entire head and engine arm may be freely turned about the bracket arm; the member G and engine arm rocked relatively to the bracket-arm at a right angle to said turning' movement of 'the entire head; and the engine-arm may be turned about the swivel (1, provided the same is used. It is Vbest to provide suitable limits to the movements aiforded by the joints g and g1.

It will be obvious that as the engine head is turned about its swivel connection with the bracket arm the relative positions et the pulleys M M are changed and there is more or less liability of the driving cord interfering with itself at certain points or with the compensating pulley K. The oint f1, however, between the inner and intermediate members of the engine head, which permits the pulleys M M being rocked laterally, overcomes this tendency and entirely prevents said interference of the driving cord. The pivot f1 is best located near said pulleys M M so that they will have the least amount of movement when moved about this pivot. In practice when the engine arm is pulled to one side the pulleys M M will first rock about the pivot f1 and then if necessary the engine head will turn about the swivel Stops ml and m2 shown in Fig. t, may be provided for limiting the lateral movement of the engine head pulleys in opposite directions. Since, in the engine herein shown and described, there is less liability of interference of the driving cord on one side than on the other, the stops are not placed opposite each other but one below the other. By this means practically the full movement is allowed on one side, while on the other side the movement is much restricted. This is clearly indicated by dotted lines in Fig. 4t.

N indicates the conductor leading from the motor to the controlling device.

The engine arm instead of being a cable, as shown, may be the arm of a cord7 or belt engine.

I claim as my invention 1. In a dental bracket engine, the combination of a supporting arm consisting of an inner section rigidly projecting from a wall plate and an outer section connected to said inner section by a vertical pivot so as to swing horizontally, and curved outwardly and downwardly, an electric motor connected to the lower extremity of the outer section of said supporting arm by a l1ori zontal pivot at a point below and in advance of the vertical pivot between the sections of said supporting arm, and a bracket arm rigidly connected t0 said electric motor, said bracket arm extending in a line intersecting the axis of the motor and the axis ofthe pivot connecting said motor and said supporting arm.

2. In a dental bracket engine, the combination of a bracket arm. anl engine head having an inner member swiveled to the outer end of said bracket arm, an intermediate member carrying a pair of idle pulleys and pivoted to said inner, member to rock llO laterally in relation thereto, and an outer for limiting the lateral movement of said member pivoted to said intermediate memintermediate member. 10 ber7 the last named pivot being disposed at In testimony whereof I affix my signature a right angle to tlieffirst named pivot so in presence of tWo Witnesses.

- that the outer member may be rocked in JOI-IN F. HAMMOND.

line with the longitudinal axis of the bracket 'i l/Vitnesses: arm, an engine arm depending from the F. C. E. PETERSEN, outer member of said engine head, and stops SAMUEL R. BARTON. 

